Wednesday, June 22, 2016
A strong summer storm currently spinning in the Gulf of Alaska as of Wednesday afternoon, courtesy of a seasonally strong Polar Vortex still dumping cool air around both US coasts, will nudge the ridge of high pressure over our area eastward, allowing a surge of moisture from the south to be drawn northward along the western periphery of the ridge. We should have more extensive cloud cover and our best chance for wetting rains by Thursday afternoon.
By Friday, the Pacific Northwest storm will have has crossed the coast, and the increased westerly winds will cut off the southern moisture feed into our area, though there will still be a chance of afternoon storms. Models move a relatively strong but dry cool front through the area Saturday morning, bringing dry breezy to windy conditions and cooler temperatures for the weekend, especially for Saturday.
Temperatures will rebound to above normal by Monday and last until midweek as the ridge of high pressure rebuilds over the west as cool air from the persistent Polar Vortex keeps troughs of low pressure over the Gulf of Alaska and the East Coast.
By midweek, yet another strong Pacific Northwest storm will again nudge the western ridge eastward, allowing moisture from the south to once again travel over our area. This moisture feed may be more persistent than the current brief surge we are currently seeing, with longer range models keeping what appears to be the beginnings of our monsoon around for the following week.
Monsoonal flow refers to the seasonal reversal of the winds, and in our case this refers to the influx of moisture as southerly winds pick up moisture originally from the Gulf of Mexico that has moved westward across Mexico and moves it over our area.